xref: /linux/drivers/mmc/core/mmc.c (revision c2f73fd07d2ce4605b404f34395eb734a7ba9967)
1 /*
2  *  linux/drivers/mmc/core/mmc.c
3  *
4  *  Copyright (C) 2003-2004 Russell King, All Rights Reserved.
5  *  Copyright (C) 2005-2007 Pierre Ossman, All Rights Reserved.
6  *  MMCv4 support Copyright (C) 2006 Philip Langdale, All Rights Reserved.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/err.h>
14 
15 #include <linux/mmc/host.h>
16 #include <linux/mmc/card.h>
17 #include <linux/mmc/mmc.h>
18 
19 #include "core.h"
20 #include "sysfs.h"
21 #include "bus.h"
22 #include "mmc_ops.h"
23 
24 static const unsigned int tran_exp[] = {
25 	10000,		100000,		1000000,	10000000,
26 	0,		0,		0,		0
27 };
28 
29 static const unsigned char tran_mant[] = {
30 	0,	10,	12,	13,	15,	20,	25,	30,
31 	35,	40,	45,	50,	55,	60,	70,	80,
32 };
33 
34 static const unsigned int tacc_exp[] = {
35 	1,	10,	100,	1000,	10000,	100000,	1000000, 10000000,
36 };
37 
38 static const unsigned int tacc_mant[] = {
39 	0,	10,	12,	13,	15,	20,	25,	30,
40 	35,	40,	45,	50,	55,	60,	70,	80,
41 };
42 
43 #define UNSTUFF_BITS(resp,start,size)					\
44 	({								\
45 		const int __size = size;				\
46 		const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1;	\
47 		const int __off = 3 - ((start) / 32);			\
48 		const int __shft = (start) & 31;			\
49 		u32 __res;						\
50 									\
51 		__res = resp[__off] >> __shft;				\
52 		if (__size + __shft > 32)				\
53 			__res |= resp[__off-1] << ((32 - __shft) % 32);	\
54 		__res & __mask;						\
55 	})
56 
57 /*
58  * Given the decoded CSD structure, decode the raw CID to our CID structure.
59  */
60 static int mmc_decode_cid(struct mmc_card *card)
61 {
62 	u32 *resp = card->raw_cid;
63 
64 	/*
65 	 * The selection of the format here is based upon published
66 	 * specs from sandisk and from what people have reported.
67 	 */
68 	switch (card->csd.mmca_vsn) {
69 	case 0: /* MMC v1.0 - v1.2 */
70 	case 1: /* MMC v1.4 */
71 		card->cid.manfid	= UNSTUFF_BITS(resp, 104, 24);
72 		card->cid.prod_name[0]	= UNSTUFF_BITS(resp, 96, 8);
73 		card->cid.prod_name[1]	= UNSTUFF_BITS(resp, 88, 8);
74 		card->cid.prod_name[2]	= UNSTUFF_BITS(resp, 80, 8);
75 		card->cid.prod_name[3]	= UNSTUFF_BITS(resp, 72, 8);
76 		card->cid.prod_name[4]	= UNSTUFF_BITS(resp, 64, 8);
77 		card->cid.prod_name[5]	= UNSTUFF_BITS(resp, 56, 8);
78 		card->cid.prod_name[6]	= UNSTUFF_BITS(resp, 48, 8);
79 		card->cid.hwrev		= UNSTUFF_BITS(resp, 44, 4);
80 		card->cid.fwrev		= UNSTUFF_BITS(resp, 40, 4);
81 		card->cid.serial	= UNSTUFF_BITS(resp, 16, 24);
82 		card->cid.month		= UNSTUFF_BITS(resp, 12, 4);
83 		card->cid.year		= UNSTUFF_BITS(resp, 8, 4) + 1997;
84 		break;
85 
86 	case 2: /* MMC v2.0 - v2.2 */
87 	case 3: /* MMC v3.1 - v3.3 */
88 	case 4: /* MMC v4 */
89 		card->cid.manfid	= UNSTUFF_BITS(resp, 120, 8);
90 		card->cid.oemid		= UNSTUFF_BITS(resp, 104, 16);
91 		card->cid.prod_name[0]	= UNSTUFF_BITS(resp, 96, 8);
92 		card->cid.prod_name[1]	= UNSTUFF_BITS(resp, 88, 8);
93 		card->cid.prod_name[2]	= UNSTUFF_BITS(resp, 80, 8);
94 		card->cid.prod_name[3]	= UNSTUFF_BITS(resp, 72, 8);
95 		card->cid.prod_name[4]	= UNSTUFF_BITS(resp, 64, 8);
96 		card->cid.prod_name[5]	= UNSTUFF_BITS(resp, 56, 8);
97 		card->cid.serial	= UNSTUFF_BITS(resp, 16, 32);
98 		card->cid.month		= UNSTUFF_BITS(resp, 12, 4);
99 		card->cid.year		= UNSTUFF_BITS(resp, 8, 4) + 1997;
100 		break;
101 
102 	default:
103 		printk(KERN_ERR "%s: card has unknown MMCA version %d\n",
104 			mmc_hostname(card->host), card->csd.mmca_vsn);
105 		return -EINVAL;
106 	}
107 
108 	return 0;
109 }
110 
111 /*
112  * Given a 128-bit response, decode to our card CSD structure.
113  */
114 static int mmc_decode_csd(struct mmc_card *card)
115 {
116 	struct mmc_csd *csd = &card->csd;
117 	unsigned int e, m, csd_struct;
118 	u32 *resp = card->raw_csd;
119 
120 	/*
121 	 * We only understand CSD structure v1.1 and v1.2.
122 	 * v1.2 has extra information in bits 15, 11 and 10.
123 	 */
124 	csd_struct = UNSTUFF_BITS(resp, 126, 2);
125 	if (csd_struct != 1 && csd_struct != 2) {
126 		printk(KERN_ERR "%s: unrecognised CSD structure version %d\n",
127 			mmc_hostname(card->host), csd_struct);
128 		return -EINVAL;
129 	}
130 
131 	csd->mmca_vsn	 = UNSTUFF_BITS(resp, 122, 4);
132 	m = UNSTUFF_BITS(resp, 115, 4);
133 	e = UNSTUFF_BITS(resp, 112, 3);
134 	csd->tacc_ns	 = (tacc_exp[e] * tacc_mant[m] + 9) / 10;
135 	csd->tacc_clks	 = UNSTUFF_BITS(resp, 104, 8) * 100;
136 
137 	m = UNSTUFF_BITS(resp, 99, 4);
138 	e = UNSTUFF_BITS(resp, 96, 3);
139 	csd->max_dtr	  = tran_exp[e] * tran_mant[m];
140 	csd->cmdclass	  = UNSTUFF_BITS(resp, 84, 12);
141 
142 	e = UNSTUFF_BITS(resp, 47, 3);
143 	m = UNSTUFF_BITS(resp, 62, 12);
144 	csd->capacity	  = (1 + m) << (e + 2);
145 
146 	csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
147 	csd->read_partial = UNSTUFF_BITS(resp, 79, 1);
148 	csd->write_misalign = UNSTUFF_BITS(resp, 78, 1);
149 	csd->read_misalign = UNSTUFF_BITS(resp, 77, 1);
150 	csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3);
151 	csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4);
152 	csd->write_partial = UNSTUFF_BITS(resp, 21, 1);
153 
154 	return 0;
155 }
156 
157 /*
158  * Read and decode extended CSD.
159  */
160 static int mmc_read_ext_csd(struct mmc_card *card)
161 {
162 	int err;
163 	u8 *ext_csd;
164 	unsigned int ext_csd_struct;
165 
166 	BUG_ON(!card);
167 
168 	if (card->csd.mmca_vsn < CSD_SPEC_VER_4)
169 		return 0;
170 
171 	/*
172 	 * As the ext_csd is so large and mostly unused, we don't store the
173 	 * raw block in mmc_card.
174 	 */
175 	ext_csd = kmalloc(512, GFP_KERNEL);
176 	if (!ext_csd) {
177 		printk(KERN_ERR "%s: could not allocate a buffer to "
178 			"receive the ext_csd.\n", mmc_hostname(card->host));
179 		return -ENOMEM;
180 	}
181 
182 	err = mmc_send_ext_csd(card, ext_csd);
183 	if (err) {
184 		/*
185 		 * We all hosts that cannot perform the command
186 		 * to fail more gracefully
187 		 */
188 		if (err != -EINVAL)
189 			goto out;
190 
191 		/*
192 		 * High capacity cards should have this "magic" size
193 		 * stored in their CSD.
194 		 */
195 		if (card->csd.capacity == (4096 * 512)) {
196 			printk(KERN_ERR "%s: unable to read EXT_CSD "
197 				"on a possible high capacity card. "
198 				"Card will be ignored.\n",
199 				mmc_hostname(card->host));
200 		} else {
201 			printk(KERN_WARNING "%s: unable to read "
202 				"EXT_CSD, performance might "
203 				"suffer.\n",
204 				mmc_hostname(card->host));
205 			err = 0;
206 		}
207 
208 		goto out;
209 	}
210 
211 	ext_csd_struct = ext_csd[EXT_CSD_REV];
212 	if (ext_csd_struct > 2) {
213 		printk(KERN_ERR "%s: unrecognised EXT_CSD structure "
214 			"version %d\n", mmc_hostname(card->host),
215 			ext_csd_struct);
216 		err = -EINVAL;
217 		goto out;
218 	}
219 
220 	if (ext_csd_struct >= 2) {
221 		card->ext_csd.sectors =
222 			ext_csd[EXT_CSD_SEC_CNT + 0] << 0 |
223 			ext_csd[EXT_CSD_SEC_CNT + 1] << 8 |
224 			ext_csd[EXT_CSD_SEC_CNT + 2] << 16 |
225 			ext_csd[EXT_CSD_SEC_CNT + 3] << 24;
226 		if (card->ext_csd.sectors)
227 			mmc_card_set_blockaddr(card);
228 	}
229 
230 	switch (ext_csd[EXT_CSD_CARD_TYPE]) {
231 	case EXT_CSD_CARD_TYPE_52 | EXT_CSD_CARD_TYPE_26:
232 		card->ext_csd.hs_max_dtr = 52000000;
233 		break;
234 	case EXT_CSD_CARD_TYPE_26:
235 		card->ext_csd.hs_max_dtr = 26000000;
236 		break;
237 	default:
238 		/* MMC v4 spec says this cannot happen */
239 		printk(KERN_WARNING "%s: card is mmc v4 but doesn't "
240 			"support any high-speed modes.\n",
241 			mmc_hostname(card->host));
242 		goto out;
243 	}
244 
245 out:
246 	kfree(ext_csd);
247 
248 	return err;
249 }
250 
251 /*
252  * Handle the detection and initialisation of a card.
253  *
254  * In the case of a resume, "curcard" will contain the card
255  * we're trying to reinitialise.
256  */
257 static int mmc_init_card(struct mmc_host *host, u32 ocr,
258 	struct mmc_card *oldcard)
259 {
260 	struct mmc_card *card;
261 	int err;
262 	u32 cid[4];
263 	unsigned int max_dtr;
264 
265 	BUG_ON(!host);
266 	WARN_ON(!host->claimed);
267 
268 	/*
269 	 * Since we're changing the OCR value, we seem to
270 	 * need to tell some cards to go back to the idle
271 	 * state.  We wait 1ms to give cards time to
272 	 * respond.
273 	 */
274 	mmc_go_idle(host);
275 
276 	/* The extra bit indicates that we support high capacity */
277 	err = mmc_send_op_cond(host, ocr | (1 << 30), NULL);
278 	if (err)
279 		goto err;
280 
281 	/*
282 	 * For SPI, enable CRC as appropriate.
283 	 */
284 	if (mmc_host_is_spi(host)) {
285 		err = mmc_spi_set_crc(host, use_spi_crc);
286 		if (err)
287 			goto err;
288 	}
289 
290 	/*
291 	 * Fetch CID from card.
292 	 */
293 	if (mmc_host_is_spi(host))
294 		err = mmc_send_cid(host, cid);
295 	else
296 		err = mmc_all_send_cid(host, cid);
297 	if (err)
298 		goto err;
299 
300 	if (oldcard) {
301 		if (memcmp(cid, oldcard->raw_cid, sizeof(cid)) != 0) {
302 			err = -ENOENT;
303 			goto err;
304 		}
305 
306 		card = oldcard;
307 	} else {
308 		/*
309 		 * Allocate card structure.
310 		 */
311 		card = mmc_alloc_card(host);
312 		if (IS_ERR(card)) {
313 			err = PTR_ERR(card);
314 			goto err;
315 		}
316 
317 		card->type = MMC_TYPE_MMC;
318 		card->rca = 1;
319 		memcpy(card->raw_cid, cid, sizeof(card->raw_cid));
320 	}
321 
322 	/*
323 	 * For native busses:  set card RCA and quit open drain mode.
324 	 */
325 	if (!mmc_host_is_spi(host)) {
326 		err = mmc_set_relative_addr(card);
327 		if (err)
328 			goto free_card;
329 
330 		mmc_set_bus_mode(host, MMC_BUSMODE_PUSHPULL);
331 	}
332 
333 	if (!oldcard) {
334 		/*
335 		 * Fetch CSD from card.
336 		 */
337 		err = mmc_send_csd(card, card->raw_csd);
338 		if (err)
339 			goto free_card;
340 
341 		err = mmc_decode_csd(card);
342 		if (err)
343 			goto free_card;
344 		err = mmc_decode_cid(card);
345 		if (err)
346 			goto free_card;
347 	}
348 
349 	/*
350 	 * Select card, as all following commands rely on that.
351 	 */
352 	if (!mmc_host_is_spi(host)) {
353 		err = mmc_select_card(card);
354 		if (err)
355 			goto free_card;
356 	}
357 
358 	if (!oldcard) {
359 		/*
360 		 * Fetch and process extended CSD.
361 		 */
362 		err = mmc_read_ext_csd(card);
363 		if (err)
364 			goto free_card;
365 	}
366 
367 	/*
368 	 * Activate high speed (if supported)
369 	 */
370 	if ((card->ext_csd.hs_max_dtr != 0) &&
371 		(host->caps & MMC_CAP_MMC_HIGHSPEED)) {
372 		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
373 			EXT_CSD_HS_TIMING, 1);
374 		if (err)
375 			goto free_card;
376 
377 		mmc_card_set_highspeed(card);
378 
379 		mmc_set_timing(card->host, MMC_TIMING_MMC_HS);
380 	}
381 
382 	/*
383 	 * Compute bus speed.
384 	 */
385 	max_dtr = (unsigned int)-1;
386 
387 	if (mmc_card_highspeed(card)) {
388 		if (max_dtr > card->ext_csd.hs_max_dtr)
389 			max_dtr = card->ext_csd.hs_max_dtr;
390 	} else if (max_dtr > card->csd.max_dtr) {
391 		max_dtr = card->csd.max_dtr;
392 	}
393 
394 	mmc_set_clock(host, max_dtr);
395 
396 	/*
397 	 * Activate wide bus (if supported).
398 	 */
399 	if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&
400 		(host->caps & MMC_CAP_4_BIT_DATA)) {
401 		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
402 			EXT_CSD_BUS_WIDTH, EXT_CSD_BUS_WIDTH_4);
403 		if (err)
404 			goto free_card;
405 
406 		mmc_set_bus_width(card->host, MMC_BUS_WIDTH_4);
407 	}
408 
409 	if (!oldcard)
410 		host->card = card;
411 
412 	return 0;
413 
414 free_card:
415 	if (!oldcard)
416 		mmc_remove_card(card);
417 err:
418 
419 	return err;
420 }
421 
422 /*
423  * Host is being removed. Free up the current card.
424  */
425 static void mmc_remove(struct mmc_host *host)
426 {
427 	BUG_ON(!host);
428 	BUG_ON(!host->card);
429 
430 	mmc_remove_card(host->card);
431 	host->card = NULL;
432 }
433 
434 /*
435  * Card detection callback from host.
436  */
437 static void mmc_detect(struct mmc_host *host)
438 {
439 	int err;
440 
441 	BUG_ON(!host);
442 	BUG_ON(!host->card);
443 
444 	mmc_claim_host(host);
445 
446 	/*
447 	 * Just check if our card has been removed.
448 	 */
449 	err = mmc_send_status(host->card, NULL);
450 
451 	mmc_release_host(host);
452 
453 	if (err) {
454 		mmc_remove(host);
455 
456 		mmc_claim_host(host);
457 		mmc_detach_bus(host);
458 		mmc_release_host(host);
459 	}
460 }
461 
462 MMC_ATTR_FN(cid, "%08x%08x%08x%08x\n", card->raw_cid[0], card->raw_cid[1],
463 	card->raw_cid[2], card->raw_cid[3]);
464 MMC_ATTR_FN(csd, "%08x%08x%08x%08x\n", card->raw_csd[0], card->raw_csd[1],
465 	card->raw_csd[2], card->raw_csd[3]);
466 MMC_ATTR_FN(date, "%02d/%04d\n", card->cid.month, card->cid.year);
467 MMC_ATTR_FN(fwrev, "0x%x\n", card->cid.fwrev);
468 MMC_ATTR_FN(hwrev, "0x%x\n", card->cid.hwrev);
469 MMC_ATTR_FN(manfid, "0x%06x\n", card->cid.manfid);
470 MMC_ATTR_FN(name, "%s\n", card->cid.prod_name);
471 MMC_ATTR_FN(oemid, "0x%04x\n", card->cid.oemid);
472 MMC_ATTR_FN(serial, "0x%08x\n", card->cid.serial);
473 
474 static struct device_attribute mmc_dev_attrs[] = {
475 	MMC_ATTR_RO(cid),
476 	MMC_ATTR_RO(csd),
477 	MMC_ATTR_RO(date),
478 	MMC_ATTR_RO(fwrev),
479 	MMC_ATTR_RO(hwrev),
480 	MMC_ATTR_RO(manfid),
481 	MMC_ATTR_RO(name),
482 	MMC_ATTR_RO(oemid),
483 	MMC_ATTR_RO(serial),
484 	__ATTR_NULL,
485 };
486 
487 /*
488  * Adds sysfs entries as relevant.
489  */
490 static int mmc_sysfs_add(struct mmc_host *host, struct mmc_card *card)
491 {
492 	int ret;
493 
494 	ret = mmc_add_attrs(card, mmc_dev_attrs);
495 	if (ret < 0)
496 		return ret;
497 
498 	return 0;
499 }
500 
501 /*
502  * Removes the sysfs entries added by mmc_sysfs_add().
503  */
504 static void mmc_sysfs_remove(struct mmc_host *host, struct mmc_card *card)
505 {
506 	mmc_remove_attrs(card, mmc_dev_attrs);
507 }
508 
509 #ifdef CONFIG_MMC_UNSAFE_RESUME
510 
511 /*
512  * Suspend callback from host.
513  */
514 static void mmc_suspend(struct mmc_host *host)
515 {
516 	BUG_ON(!host);
517 	BUG_ON(!host->card);
518 
519 	mmc_claim_host(host);
520 	if (!mmc_host_is_spi(host))
521 		mmc_deselect_cards(host);
522 	host->card->state &= ~MMC_STATE_HIGHSPEED;
523 	mmc_release_host(host);
524 }
525 
526 /*
527  * Resume callback from host.
528  *
529  * This function tries to determine if the same card is still present
530  * and, if so, restore all state to it.
531  */
532 static void mmc_resume(struct mmc_host *host)
533 {
534 	int err;
535 
536 	BUG_ON(!host);
537 	BUG_ON(!host->card);
538 
539 	mmc_claim_host(host);
540 	err = mmc_init_card(host, host->ocr, host->card);
541 	mmc_release_host(host);
542 
543 	if (err) {
544 		mmc_remove(host);
545 
546 		mmc_claim_host(host);
547 		mmc_detach_bus(host);
548 		mmc_release_host(host);
549 	}
550 
551 }
552 
553 #else
554 
555 #define mmc_suspend NULL
556 #define mmc_resume NULL
557 
558 #endif
559 
560 static const struct mmc_bus_ops mmc_ops = {
561 	.remove = mmc_remove,
562 	.detect = mmc_detect,
563 	.sysfs_add = mmc_sysfs_add,
564 	.sysfs_remove = mmc_sysfs_remove,
565 	.suspend = mmc_suspend,
566 	.resume = mmc_resume,
567 };
568 
569 /*
570  * Starting point for MMC card init.
571  */
572 int mmc_attach_mmc(struct mmc_host *host, u32 ocr)
573 {
574 	int err;
575 
576 	BUG_ON(!host);
577 	WARN_ON(!host->claimed);
578 
579 	mmc_attach_bus(host, &mmc_ops);
580 
581 	/*
582 	 * We need to get OCR a different way for SPI.
583 	 */
584 	if (mmc_host_is_spi(host)) {
585 		err = mmc_spi_read_ocr(host, 1, &ocr);
586 		if (err)
587 			goto err;
588 	}
589 
590 	/*
591 	 * Sanity check the voltages that the card claims to
592 	 * support.
593 	 */
594 	if (ocr & 0x7F) {
595 		printk(KERN_WARNING "%s: card claims to support voltages "
596 		       "below the defined range. These will be ignored.\n",
597 		       mmc_hostname(host));
598 		ocr &= ~0x7F;
599 	}
600 
601 	host->ocr = mmc_select_voltage(host, ocr);
602 
603 	/*
604 	 * Can we support the voltage of the card?
605 	 */
606 	if (!host->ocr) {
607 		err = -EINVAL;
608 		goto err;
609 	}
610 
611 	/*
612 	 * Detect and init the card.
613 	 */
614 	err = mmc_init_card(host, host->ocr, NULL);
615 	if (err)
616 		goto err;
617 
618 	mmc_release_host(host);
619 
620 	err = mmc_add_card(host->card);
621 	if (err)
622 		goto remove_card;
623 
624 	return 0;
625 
626 remove_card:
627 	mmc_remove_card(host->card);
628 	host->card = NULL;
629 	mmc_claim_host(host);
630 err:
631 	mmc_detach_bus(host);
632 	mmc_release_host(host);
633 
634 	printk(KERN_ERR "%s: error %d whilst initialising MMC card\n",
635 		mmc_hostname(host), err);
636 
637 	return err;
638 }
639 
640